How to extract URL parameters from a URL with Ruby or Rails?

I have some URLs, like

http://www.example.com/something?param1=value1&param2=value2&param3=value3

and I would like to extract the parameters from these URLs and get them in a Hash. Obviously, I could use regular expressions, but I was just wondering if there was easier ways to do that with Ruby or Rails. I haven't found anything in the Ruby module URI but perhaps I missed something.

In fact, I need a method that would do that:

extract_parameters_from_url("http://www.example.com/something?param1=value1&param2=value2&param3=value3")#=> {:param1 => 'value1', :param2 => 'value2', :param3 => 'value3'}

Would you have some advices?